This invention relates to a process for the production of polyester-silicate resinous products by chemically reacting a silicic acid with a .omega.-hydroxy acid or by reacting a silicic acid with a dibasic acid and a dihydric alcohol by heating the mixture in the presence of an alkali catalyst.
For the purpose of this invention, the products produced by this instant process will be named polyester-silicate resinous products.
The silicic acid compound used in this process may be produced by the chemical reaction of a dry alkali metal metasilicate with a mineral acid or an acid hydrogen containing salt. The silicic acid compound used in the following examples was produced by reacting dry granular alkali metal metasilicate with an hydrogen containing acid salt or a concentrated mineral acid. The white granular silicic acid is washed with water, filtered, and then air dried at 25.degree. to 75.degree. C.
The white granular silicic acid was analyzed by Infrared Analysis, using the IR KBr disc method. The Infrared Analysis was very similar to that obtained with Mallinckrodt's hydrated silica standard, except for the area which shows the presence of Si-H bonds. The Mallinckrodt's hydrated silica (SiO.sub.2.xH.sub.2 O) has a molecular weight of 60.09.xH.sub.2 O. The said silicic acid contains an active hydrogen which will reduce silver nitrate in an aqueous solution; this is evidence that Si-H bonds are present.
When the said silicic acid is heated to much above 105.degree. C, silicon dioxide with a molecular weight of about 60 is produced. The molecular weight was determined from the boiling point elevation of said silicic acid in a 6N hydroxide solution and indicated a molecular weight of 78 .+-. 25 gm/mol. This type of reaction solution normally changes the molecular species. However, this would seem to indicate the absence of a polymeric form of silicate. This analysis may indicate a possible formula of HSi(OH).sub.3 (orthosilicoformic acid) and SiO.sub.2.xH.sub.2 O (hydrated silica). The orthosilicoformic acid, when dried, will lose water to form siliconformic acid (H.SiO.OH). Hydrated silica produced by any of the commonly known processes may be used in this invention.
The silicic acid compound will react chemically with a dihydric or polyhydric alcohol by heating the mixture in the presence of an alkali catalyst to produce an organic alcohol silicate compound which will react chemically with a dibasic acid to produce a polyestersilicate resinous product. The silicic acid compound will react chemically with a dibasic acid by heating the mixture in the presence of an alkali catalyst to produce an organic acid silicate.
The silicic acid will react chemically with either saturated and/or unsaturated polyfunctional acids and alcohols to eventually form cross-linked, three dimensional esters. The unsaturated polyester silicate may be cured with a small amount of a peroxide. An excess of the dihydric alcohol may be used in the production of polyester-silicate resinous products. The aliphatic and aromatic dicarboxylic acids may be used in this process. The drying oil acids may be used in this process.
The unsaturated polyester-silicate resinous products may be reacted with vinyl monomers to produce a cross-linked, three-dimensional resin. The resin is cured by the use of free-radical initiators, such as peroxides and azo compouds. The action of the organic peroxide can be modified by activators and promoters.
The polyester-silicate polymers may be utilized in coatings for linoleum, leather, fabrics, and rubber. They may be utilized in paints, lacquers, metal primers, caulking compounds and water-emulsion paints. They may be copolymerized with a vinyl monomer to produce hard, solid, useful objects, or they may be used in conjunction with a reinforcing filler, such as glass fiber, paper or cloth to produce a laminate of outstanding strength and durability. They may be used as a molding powder, as an adhesive and as impregnants. They may be chemically reacted with isocyanate to produce polyurethane silicate resin and foams.